At about 11 pm EST on January 22, 2012, Sunspot 1402 experienced a M9 class solar flare. This is just below the highest X class of solar flare. This solar flare unleashed at least a billion megatons of TNT equivalent in energy, reached millions of degrees in temperature and produced a coronal mass ejection (CME) that erupted off the Sun and headed for Earth and Mars.
This solar flare event has produced the strongest solar radiation storm since 2005. The storm began almost immediately as radiation from the event reached Earth. The CME is traveling at 1400 miles per second and has taken some time to travel the 93 million miles from the Sun to the Earth.
Sunspot 1402 M9 Solar Flare Event as Seen by Solar Dynamics Observatory
Solar flares erupt when magnetic fields that occur in sunspots get twisted and the energy stored in these magnetic fields is suddenly released. These events are the largest explosions in the solar system. CME's are sometimes created by a solar flare and are huge bubbles of gas threaded with magnetic file lines. They blow off of the Sun for several hours and head out into space.
This solar radiation storm is a class S3, which is a "strong" solar radiation storm (SRS) classification; the scale goes to S5 which is an "extreme" solar radiation storm and can have significant effects on spacecraft and here on Earth. Read More About the Scale: http://www.swpc.noaa.gov/NOAAscales/index.html#SolarRadiationStorms
An S3 SRS can affect spacecraft in orbit and everyday items such as GPS, the electrical power grid and communications. The astronauts on the International Space Station are safe and have procedures and the ability to "shelter in place" if required.
We all know Earth has weather, but this event brings home the fact that we are affected by "space weather" as well. Just as it does here on Earth, the Sun powers space weather. We also have dedicated space weather professionals, who just like their terrestrial meteorological counterparts, monitor space weather 24x7.
In fact, the National Oceanographic and Atmospheric Administration (NOAA), the government agency that is responsible for the National Weather Service (NWS), has under the auspices of the NWS, a Space Weather Prediction Center (SWPC) http://www.swpc.noaa.gov/.
While the solar radiation storm is still occurring but subsiding, the CME ejected by the Sun is predicted to hit Earth at 9 am EST January 24, 2012. According to the SPWC, "The SWPC forecast is for Moderate (G2) level geomagnetic storming with G3 levels possible. An animation from the WSA-Enlil model showing the Coronal Mass Ejection and its trip from the Sun to the Earth is available here. Updates will be posted here as we learn more or follow us on Facebook."
There is no danger to us or the astronauts from this SRS and CME event. These events are likely to occur more frequently and perhaps get even stronger as the Sun nears Solar Maximum, currently predicted to occur in 2013-2014. This is an 11 year cycle that the Sun goes through in which sunspots, solar flares and associated events undergo a minimum phase that builds to a maximum phase and then back to minimum. This is a normal part of our star's life cycle and with the fleet of spacecraft we now have monitoring the Sun we are better equipped than ever to monitor our space weather and be warned of significant events.
Read More About It: http://www.myfoxdc.com/dpp/news/strongest-solar-storm-since-2005-hitting-earth-012312 and http://www.nasa.gov/mission_pages/sunearth/news/News012312-M8.7.html
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